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How to convert date from react calendar in the dd/mm/yyyy format?

I am using react-calendar , Here I am getting a date in the following format
Wed Feb 02 2022 00:00:00 GMT+0530 (India Standard Time)
Now I am trying to convert it to dd/mm/yyyy. is there any way though which I can do this ?
Thanks.

The native Date object comes with seven formatting methods. Each of these seven methods give you a specific value -
toString() : Fri Jul 02 2021 14:03:54 GMT+0100 (British Summer Time)
toDateString(): Fri Jul 02 2021
toLocaleString() : 7/2/2021, 2:05:07 PM
toLocaleDateString() : 7/2/2021
toGMTString() : Fri, 02 Jul 2021 13:06:02 GMT
toUTCString() : Fri, 02 Jul 2021 13:06:28 GMT
toISOString() : 2021-07-02T13:06:53.422Z
var date = new Date();
// toString()
console.log(date.toString());
// toDateString()
console.log(date.toDateString());
// toLocalString()
console.log(date.toLocaleString());
// toLocalDateString()
console.log(date.toLocaleDateString());
// toGMTString()
console.log(date.toGMTString());
// toGMTString()
console.log(date.toUTCString());
// toGMTString()
console.log(date.toISOString());
Format Indian Standard time to Local time -
const IndianDate = 'Wed Feb 02 2022 00:00:00 GMT+0530 (India Standard Time)';
const localDate = new Date(IndianDate).toLocaleDateString();
console.log(localDate);

You could use the methods shown in this blogpost https://bobbyhadz.com/blog/javascript-format-date-dd-mm-yyyy from Borislav Hadzhiev.
You could a new date based on your calendar date and afterwards format it:
function padTo2Digits(num) {
return num.toString().padStart(2, '0');
}
function formatDate(date) {
return [
padTo2Digits(date.getDate()),
padTo2Digits(date.getMonth() + 1),
date.getFullYear(),
].join('/');
}
console.log(formatDate(new Date('Wed Feb 02 2022 00:00:00 GMT+0530 (India Standard Time)')));

This is JavaScript default date format.
You can use libraries like momentjs, datefns, etc to get the result.
For example, if you are using momentjs:-
moment(date).format('dd/mm/yyyy);
Or if you don't want to use any third-party library you can get the result from JavaScript's default date object methods.
const date = new Date();
const day = date.getDate() < 10 ? 0${date.getDate()} : date.getDate();
const month = date.getMonth() + 1 < 10 ? 0${date.getMonth() + 1} : date.getDate() + 1;
const year = date.getFullYear();
const formattedDate = ${day}/${month}/${year};

Google Apps Script add month to a date until specific date is reached

I have the following code using Google Apps Script, but when I log it out I get the following results. I want GAS to log the next month and stop once it gets to "lastDateofYear ". For whatever reason, the year doesn't change in my results, it just keeps repeating the current year. Please help.
var thisDate = "Mon Dec 20 00:00:00 GMT-06:00 2021";
var nextYear = Number(currentYear)+1;
var lastDateofYear = new Date("12-31-"+nextYear);
for(var i=thisDate; i <= lastDateofYear; ){
var currentiDate = new Date(i);
var month = currentiDate.getMonth()+1;
i.setMonth((month) % 12);
i.setDate(currentiDate.getDate());
Logger.log(currentiDate);
}
RESULTS:
Mon Dec 20 00:00:00 GMT-06:00 2021
Wed Jan 20 00:00:00 GMT-06:00 2021
Sat Feb 20 00:00:00 GMT-06:00 2021
Sat Mar 20 00:00:00 GMT-05:00 2021
Tue Apr 20 00:00:00 GMT-05:00 2021
Thu May 20 00:00:00 GMT-05:00 2021
Sun Jun 20 00:00:00 GMT-05:00 2021
Tue Jul 20 00:00:00 GMT-05:00 2021
Fri Aug 20 00:00:00 GMT-05:00 2021
Mon Sep 20 00:00:00 GMT-05:00 2021
Wed Oct 20 00:00:00 GMT-05:00 2021
Sat Nov 20 00:00:00 GMT-06:00 2021
Mon Dec 20 00:00:00 GMT-06:00 2021
Wed Jan 20 00:00:00 GMT-06:00 2021
Sat Feb 20 00:00:00 GMT-06:00 2021
Sat Mar 20 00:00:00 GMT-05:00 2021
Tue Apr 20 00:00:00 GMT-05:00 2021

As I understand it, you want to print each month from the given date to the last month of the next year of the given date in the log.
You can do this in the following code:
let start = new Date("Mon Dec 20 00:00:00 GMT-06:00 2021");
let currentYear = new Date().getFullYear();
let nextYear = currentYear + 1;
let end = new Date(nextYear, 11, 31);
while (start <= end) {
// You can use Logger.log() here if you want. I use console.log() for demo purpose
console.log(new Date(start).toDateString());
start.setMonth(start.getMonth() + 1);
}
If I got any part wrong, feel free to point it out to me in the comments.

There is a lot to say about your code:
var thisDate = "Mon Dec 20 00:00:00 GMT-06:00 2021";
That timestamp format is not supported by ECMA-262, so don't use the built–in parser to parse it, see Why does Date.parse give incorrect results?
var nextYear = Number(currentYear)+1;
Where does currentYear come from?
var lastDateofYear = new Date("12-31-"+nextYear);
Parsing of an unsupported format, see above. In Safari it returns an invalid date.
for(var i=thisDate; i <= lastDateofYear; ){
Sets i to the string value assigned to thisDate. Since lastDateOfYear is an invalid date in Safari and Firefox, so the test i <= NaN is never true and the loop is never entered.
var currentiDate = new Date(i);
Parses i, see above.
var month = currentiDate.getMonth()+1;
i.setMonth((month) % 12);
i is a string, which doesn't have a setMonth method so I'd expect a Type error like "i.setMonth is not a function" if the loop actually runs.
i.setDate(currentiDate.getDate());
Another Type error as above (but it won't get this far).
Logger.log(currentiDate);
}
It seems you want to sequentially add 1 month to a date until it reaches the same date in the following year. Trivially, you can just add 1 month until you get to the same date next year, something like:
let today = new Date();
let nextYear = new Date(today.getFullYear() + 1, today.getMonth(), today.getDate());
let result = [];
do {
result.push(today.toString());
today.setMonth(today.getMonth() + 1);
} while (today <= nextYear)
However, adding months is not that simple. If you add 1 month to 1 Jan, you'll get 2 or 3 Mar depending on whether it's a leap year or not. And adding 1 month to 31 Aug will return 1 Oct.
Many "add month" functions check to see if the date rolls over an extra month and if it does, set the date back to the end of the previous month by setting the date to 0, so 31 Jan + 1 month gives 28 or 29 Feb.
But if you cycle over a year using that algorithm, you'll get say 31 Jan, 28 Feb, 28 Mar, 28 Apr etc. rather than 31 Jan, 28 Feb, 31 Mar, 30 Apr, etc.
See JavaScript function to add X months to a date and How to add months to a date in JavaScript?
A more robust way is to have a function that adds n months to a date and increment the months to add rather than the date itself so the month–end problem can be dealt with separately for each addition, e.g.
/* Add n months to a date. If date rolls over an extra month,
* set to last day of previous month, e.g.
* 31 Jan + 1 month => 2 Mar, roll back => 28 Feb
*
* #param {number} n - months to add
* #param {Date} date - date to add months to, default today
* #returns {Date} new Date object, doesn't modify passed Date
*/
function addMonths(n, date = new Date()) {
let d = new Date(+date);
let day = d.getDate();
d.setMonth(d.getMonth() + n);
if (d.getDate() != day) d.setDate(0);
return d;
}
/* return array of n dates at 1 month intervals. List is
* inclusive so n + 1 Dates returned.
*
* #param {Date} start - start date
* #param {number} n - number of months to return
* #returns {Array} array of Dates
*/
function getMonthArray(n, start = new Date()) {
let result = [];
for (let i=0; i<n; i++) {
result.push(addMonths(i, start));
}
return result;
}
// Examples
// Start on 1 Dec
getMonthArray(12, new Date(2021,11,1)).forEach(
d => console.log(d.toDateString())
);
// Start on 31 Dec
getMonthArray(12, new Date(2021,11,31)).forEach(
d => console.log(d.toDateString())
);
The functions don't attempt to parse timestamps to Dates, that responsibility is left to the caller.

javascript - date difference should be zero but it is 18 hours

This one has stumped me. It should be so simple I would think. I am doing some very simple date subtraction in Javascript. I am subtracting the same dates and I would think it would give zero hours, but it gives 18 hours.
let inDate = new Date('Tue Aug 27 2019 00:00:00 GMT-0500 (Central Daylight Time)').getTime();
let outDate = new Date('Tue Aug 27 2019 00:00:00 GMT-0500 (Central Daylight Time)').getTime();
document.getElementById('date').innerHTML = new Date(outDate - inDate);
<div id='date'>
</div>
In case it produces different results based on where you are, the result I am getting is this:
Wed Dec 31 1969 18:00:00 GMT-0600 (Central Standard Time)

This is due to your timezone. If you convert to GMT String before print it the time will be correct. (Jan 01, 1969 00:00:00)
new Date(outDate - inDate).toGMTString()
You should see the correct date.
let inDate = new Date('Tue Aug 27 2019 00:00:00 GMT-0500 (Central Daylight Time)').getTime()
let outDate = new Date('Tue Aug 27 2019 00:00:00 GMT-0500 (Central Daylight Time)').getTime()
console.log(new Date(inDate - outDate).toGMTString())

How to use .replace to replace the string in a array

need to replace GMT+0530 (India Standard Time) to IST
dynamically for multiple array list
for now my array list has 6 entries. need to replace for all the array list .
function getTimeAccordingtoTimeZone(utc){
utc = new Date(Date.parse(utc));
var dateUTC = utc ;
var dateIST = new Date(dateUTC);
//date shifting for IST timezone (+5 hours and 30 minutes)
var current_time_zone = getCurrentTimeZone();
var hour_diff = parseInt(current_time_zone);
var minute_diff = current_time_zone - hour_diff;
minute_diff = minute_diff*60;
dateIST.setHours(dateIST.getHours() + hour_diff);
dateIST.setMinutes(dateIST.getMinutes() + minute_diff);
var new_date = dateIST;
return new_date;
}
new_date returns
Tue Jan 15 2019 22:49:04 GMT+0530 (India Standard Time)
Tue Jan 15 2019 22:49:04 GMT+0530 (India Standard Time)
Tue Jan 15 2019 22:49:04 GMT+0530 (India Standard Time)
Tue Jan 15 2019 22:49:04 GMT+0530 (India Standard Time)
Tue Jan 15 2019 22:49:04 GMT+0530 (India Standard Time)
Tue Jan 15 2019 22:49:04 GMT+0530 (India Standard Time)

I'd propose you use moment JS to format the string.
In your case, the following code will help you:
const moment = require('moment');
date = moment();
const dateString = `${date.format('ddd MMM DD YYYY HH:mm:ss')} IST`
console.log(dateString);
MomentJs Documentation

How to convert the Full UTC time to yyyymmdd format using javascript

here how can i convert the
[Sun Jul 15 2018 17:48:13 GMT+0530 (India Standard Time), Sun Jul 22 2018 17:48:13 GMT+0530 (India Standard Time)]
to 20180715 using javascript
here a variable named DateData is storing the above two dates
DateData:Date[];
After selecting the from the datetime picker i storing the data in the DateData
now i am trying to convert the variable using DateData.toISOstring or DateData.toDate() also not working displaying as unable to convert the dataData to Date Format

Perhaps something like this
function sqlDate(dat)
{
return dat.toISOString().substr(0,10).replace('-','');
}

There you go. :)
function convertDates(dateArr) {
var newDateArray = [],
dateObj;
for (var i=0; i<dateArr.length; i++) {
dateObj = new Date(dateArr[i]);
newDateArray.push(dateObj.getFullYear() + '' + dateObj.getMonth() + '' + dateObj.getDate());
}
return newDateArray;
}
var dateArr = ['Sun Jul 15 2018 17:48:13 GMT+0530 (India Standard Time)', 'Sun Jul 22 2018 17:48:13 GMT+0530 (India Standard Time)'];
console.log(convertDates(dateArr));

function formatDate(date){
if(date instanceof Date) date = new Date(date);
var fullZero = s => s.toString().length ===1 ?'0'+s :s.toString();
return `${date.getFullYear()}${fullZero(date.getMonth()+1)}${fullZero(date.getDate())}`;
}
formatDate(new Date) // -> "20180722"
If you have an array of Date, use dateData.map(formatDate) to format it.

Try splitting on the "T" like this snippet:
var d = new Date();
// => d.toISOString() show 2019-02-01T06:38:21.990Z
console.log(d.toISOString().split("T")[0].replace(/-/g, ''));
or you can use a JavaScript library called date-and-time for the purpose.
let now = date.format(new Date(), 'YYYYMMDD');
console.log(now);
<script src="https://cdn.jsdelivr.net/npm/date-and-time/date-and-time.min.js"></script>